From: "Shot (Piotr Szotkowski)" <shot@...>
Date: 2008-10-22T02:46:40+09:00
Subject: Re: what's different between self.method and class << self?

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Zhenning Guan:

> we can define a instance method in lots way.
> mostly, I saw people define like this:
> 1.
> class A
>   def self.class_method
>   #some code here....
>   end
> end

> 2.
> class A
>   class << self
>     def class_method
>     #some code here....
>     end
>   end
> end

> the question confused me is what's the advantage of doing this in 2?

You can work on the singleton=E2=80=99s properties with attr_* methods:

class Example
  class << self
    attr_accessor :prop
  end
end

(With the first approach you=E2=80=99d have to define self.prop and
self.prop=3D to be able to write code like Example.prop =3D 'value'.)

-- Shot
--=20
Damn, I need to rant, not whimper. Someone bring me a user.   -- Wayne Pasc=
oe

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